Sound-record.



V. H. E ON. SOUND D. APPLICATION rum) MAY 18, 1911.

Patented Aug. 18, 1914.

mum

V. H. EMERSON. SOUND RECORD. APPLIOATION rmm MAY 18, m1.

Patented Aug. 18, 1914.

q vi/f/we/aoeo: 5 wue when 1,; AIS aflo'cmuas M G {jass'lz rJNITEDSTATES VICTOR H. EMERSON, OF NEW COMPANY. OF BRIDGEPORT,

AMERICAN GRAPHOPHONE sounnnncoma.

To all whom it may concern:

Be it known that I, Vroron H. EMERSON, a citizen of the United States ofAmerica, and a resident of New York city, New York, have invented a newand useful Improve-- ment in Sound-Records, which invention is fully setforth in the following specification.

This invention relates to sound-records for talking-machines and theproduction thereof. It is particularly adapted for records in the formof a flat tablet or disk having the record-groove of practicallyuniformdepth arranged thereon inspiral form and characterized by lateralirregularities corresponding to sound-waves (commonly known as zigzagdisk records); but the invention is likewise applicable to disk recordshaving the spirally-arranged record-groove of varying depth (commonlyknown as the up-and-down records) and the invention is also applicableto recordrooves of either type upon tablets of cylinrical-or other form.

This invention is based upon my novel manner or process of producing theoriginal sound-record, and the use of my novel recording-stylus, which,however, are not here claimed.

The invention here claimed consists of my novel sound-records themselves(both original records and also commercial records obtained therefrom).

My invention consists further in the various details and featureshereinafter set forth and claimed.

The invention will be best understood by reference to the annexeddrawings which illustrate various portions thereof.-

In these drawings,-Fi'gures l and'2 are elevations, indicatingconventionallthe production of original sound-records y my invention.Fig. 3 1s a side-view on'an enlarged scale, showing my recording-stylusin the preferred method of using itl a modification ofthe same. Fig. 5is a horizontal section through the stylus atthe surface of the tabletin Fig. 3. Fig. 6 repre-' sents conventionally an electroplating bath,and Fig. 7 a press, as practical means for obtaining copies of theoriginal. Fig. 8 isa plan, upon a greatly-exaggerated scale,illustrating conventionally a portion of' my new Specification ofLetters Patent.-

Appitcationfiled May 18L 1911.

out any cutting-edges,

cate the preferred tablet, the stylus cleaves Fig. this Patented Aug.is, rare. Serial No. 628,029.

record groove; and Fig. 9 is a similar conventional plan of therecord-groove of the priorart.

As my invention is intended primarily for zigzag disk records (thoughapplicable to other forms and types) I will describe it in thatconnection.

Referring to' Figs. 1, 3 and 5, -'1 represents the flat record-tablet,which broadly speaking is of the wax-like composition commonly used inthis art. 2 represents a sound box, upon which the new stylus 3 ismounted in the ordinary manner. The tablet- 1 is carried upon the usualturntable and revolves in the direction indicated by the arrow.

My new stylus has the operating portion or tip in the form of a cone,being rounded off uniformly on all sides, as indicated in Fig. 3. It isnot essential that this recording-tip should be a precise mathematicalcone. It is sufficient that in cross section it should be practicallysymmetrical, and withas indicated in Fig. 5, where it is practicallyelliptical, being a sec tion through acone by a plane at an angle to theaxis of the cone. Figs. 1 and 3 indimanncr of using this stylus inmaking the record. The stylus is shown at an angle of about 45 (more orless) to the surface of the tablet. The effect of' revolving theturntable and tablet 1 in the direction shown in Fig. 1 is the same asif the stylus'3'were shoved point foremost. In its passage through thematerial ofthe or plows its way, removingthe material from the tablet inthe form of a fine thread or shaving, or under favorable conditions asseparate particles in powdery form (according to the consistency ofthe'material). Apparently the extreme tip or acute point-of the stylus 3first cleaves its way, crushing the material out as a plow, whilethe'successive wider portions of the stylus (above'the extreme tlp)serve to simultaneousl crush and smooth or polish the side-walls oi therecord-groove. As the result of this operation, I have recordedselections which, when copied in more durable form and audiblyreproduced, manifest remarkably superior quality. This method ofproducing the original record,wherein the able,as distinguished materialis removed entirely from the tablet to produce the record-groove isdistinguished from the cutting-out of U. S. Letters-Patent No. 896,059,granted Aug. 11, 1908; and my new process is distinguished on the otherhand from the displacing operation described in U. S. Letters-Patent No.941,010 granted Nov. 23, 1909, according to whic latter patent thematerial is not removed from the tablet but merely shoved to either sideof the recordgroove. 7

Instead of shoving the stylus 3 through the surface of the tablet asindicated in Figs. 1 and 3, it may be dragged through the tablet asindicated in Fig. 4; and instea of employing a flat tablet or disk 1, asindicated in Fig. 1, I may employ a cylindrical tablet 1, as indicatedin Fig. 2; and instead of having the sound-box with its stylus ar:ranged to vibrate laterally (in the plane of the surface of the tablet)as in Fig. l, the parts may be arranged asin Fig. 2 so that the stylus 3will vibrate to and fro to produce the up-and-down type ofrecord-groove. In employing my invention, the up-anddown type ofrecord-groove may be applied to a disk tablet, or the zigza type to acylindrical tablet. This metho .of producing original records may bepractised with any usual record-composition; but, better results can beobtained if the composition be especially adapted for the purpose. mongother compositions, I have employed with success a mixture of about twoparts beeswax and two parts stearic acid with one part of carnauba wax;although these proportions may be varied greatly and differentingredients employed. In-using that particular formula I have found thatthe same is liable to solidify with more or less crystallization, whichis objectionable; and I have found that this objection may be overcomeby pouring the melted mixture just refered to over a flat metal plate,to obtain a comparatively thin layer, which is suitable for the purpose.Of course, immediately before using a record-tablet for recording, thesurface thereof is turned true by a shaving-knife in the usual mannerpractised in the production of disk soundrecords.

The characteristics, which a suitable record-material should present,are that the material must be crisp, or crumbly, or crushable, orchalky, or short, or frifrom a yielding, spongy, tenacious, cohesive,sticky, and pully. material. The function or operation of my newrecording-stylus appears to be to crush or break-up operation is bestcarried on upona material of the character above described asfriable,whereas in a material of the yielding and tenacious character,the particles re- .terial itself, by which I mean the the material,which moved to produce the record-groove would adhere or cling to thetablet and thereby deface the sound-record; moreover, th

body of the tablet, would tend to spring back and to.that extent mar ordeface or obliterate the impressions already produced by the stylus.

Having obtained an original sound-record as above indicated, by means ofthe stylus above described (when employed in'the manner set forth), andin a material of the character described-such original soundrecords canbe employed for direct, audible reproduction. But preferably duplicatesor copies will be made therefrom in any desired manner. For obtainingduplicates of the disk type, I would employ the electroplating processindicated in Fig. 6, followed by pressing the electroplates therebyobtained into suitable thermo-plastic material, as indicated in Fig. 7.This process is fully set forth in U. S. Letters-Patent No. 688,739,granted Dec. 10, 1901.

Various processes of duplicating have been employed for copyingcylindrical records; and the particular method employed for the purposewith eitherform of record is not material so long, as duplicates orcopies of my original record-goove are obtained.

' With regard to the record-tablet and its quality, I have found thatit. is sometimes desirable to give the surface of the recordtablet apreliminary coating of graphite, 100

finely-powdered graphite being carefully brushed over the surface tocoat'the same thoroughly. This serves as a lubricant, and permits thestylus to vibrate with less opposition so as to produce that gives amore true indication of the original sound-waves. When this graphitingis employed, the recording-stylus seems to carry more or less of thegraphite down with it, the graphite bein found as a thin, 110

faint coating upon the bottom and sidewalls of the record-groove.However, when the material is otherwise of the proper consistency, Iprefer not to use the graphiting step above referred to--in fact I findit not 115 so desirable. Referring now to the greatly exaggeratedconventional views of Figs. 8 and '9: 21, 22,

23, etc. indicate different positions occupied by my recording-stylus inproducing the 120 record-groove whose side-walls are'indicated by 31 and32. It is obvious that if the groove be measured by a line extending atright angles from any particular portion of the side-wall of therecord-groove, tance across or the effective width of the groove isconstant,--being the diameter of the recording-stylus. On the otherhand, referring to Fig. 9, the successive positions of the flattenedrecording-stylus heretofore 130 a record-groove the disemployed, areindicated by 41, 41, etc.; and the side-walls of the record-grooveproduced thereby are, indicated by 51 and 52. It is obvious thatmeasured transversely by the parallel lines corresponding to the widthof this old recording-stylus, this recordgroove is of constant Width;but measured by a line at right angles from any particular portion ofthe side-wall of the 01d record-groove, the same will be found to be ofvarying width,-being Wider where the recordingstylus 41 was advancingstraight ahead, and being narrower where the recording-stylus 41 wasadvancing in an oblique direction. Consequently the record-grooves ofthe records heretofore known are not of constant effective width. Thisis one distinctive feature of my sound-record; namely, that it has arecord-groove of constant effective width. This is-valuable inreproducing. With the prior records it is obvious that thereproducing-stylus must be no larger than the narrowest portion of therecord-groove,-which means that the reproducing-stylus must be ofsmaller dimensions than the recording-stylus; and this means that thereproducing-stylus does not fit truly in the groove, and is liable tomore or less rattle in reproducing. Or if a reproducing-stylus beemployed of substantially the same dimensions as the recordingstylus,then in reproducing it has to tear its way through the narrower portionsof the record-groove, walls or record-surface of those portions of thegroove, but likewise wears or grinds the extreme tip of the needle. Inmy new record-groove, on the contrary, a reproducingstylus of preciselythe same size and shape as the recording-stylus may be employed, and itWill follow freely and intimately throughout the entire length of therecordgroove with less wear upon the needle itself and upon the walls ofthe groove, thereby prolonging the life of both.

It might be imagined that the keen cuttlng-edgesndicated in therecording-stylus heretofore employed are more eflicient in that they canproduce the more minute indentations corresponding to the overtones, butthis is not of any importance. Assuming for the moment that it is true,yet the reproducing-stylus, if it cannot enter the more minuteindentations, would not be able to reproduce from them. But, as a matterof fact, my rounded and non-cutting recording-stylus produces just thesame number of alternating concavities and convexities in the side-wallsof the groove, and of just the same frequency, and of the same relativedepths and shallownesses, as in case of the keen-edged cutting-out tool.And the audible reproductions are even more faithful, because thereproducing-stylus (being of the same shape and size as the recorders)can which not only injures the enter wherever the recorder went; and,further, the side-walls of my newgroove seem smoother than the cut wallsof the prior art.

I have thus described my invention and an embodiment thereof, withconsiderable detail, but merely for the sake of clearness, since myinvention is not limited to the precise details thus set forth. Thespirit of my invention involves each of the following broad features:the employment for recording purposes of a stylus which is practicallysymmetrical in cross-section and without any cutting-edges and withoutbeing flattened longitudinally of the recordgroove; the employment ofsuch. stylus in crushing out and removing the material from the tabletwhich forms the recordgroove as distinguished from cutting out of thematerial and as distinguished from 85 merely displacing the materialwithout removing it from the tablet; and the employment of said stylusin such a method with a material which I may designate as friable. And,in case of zigzag records, the production of a record-groove which shallhave a constant effective width.

My invention consists further in producing commercial duplicates orcopies, in hard and more durable material, of such recordgroove ofconstant effective width; and in a commercial sound-record having thatcharacteristic. Finally, the extreme tip of my new stylus produces asharply-defined track in the extreme bottom of the grooves, which 100the tip of the reproducer follows with utmost fidelity; that is to say,the opposite walls of my new record-groove converge to a narrow line, sothat the groove in cross section may be defined as ll-shaped.

Having thus described my invention, I claim 1. A sound-record of thezigzag type consisting of a tablet of friable material having arecord-groove formed therein by crushing 110 out and removing thematerial to produce a groove of constant effective width.

24A sound-record consisting of a tablet of friable material having arecord-groove of substantially uniform depth and of con- 115 stanteffective width and formed by crushing out and removing the materialfrom. said tablet.

3. A sound-record consisting of a tablet of friable material having arecord-groove of substantially uniform depth and of constant effectivewidth, the undulations of which are formed directly in accordance withthe vibrations from a source of sound.

4. A sound-record consisting of a tablet of friable material having arecord-groove formed therein by crushing out and removing the material.

5. A sound-record consisting of a tablet having a substantially V-shapedrecord- 13 groove of uniform depth and constant efiective width, theundulations of which are formed directly in accordance with thevibrations from a source of sound, said record-groove beingcharacterized by having its bottom consisting of a sharply definedzigzag line corresponding to sound-waves.

6. A sound-record consisting of a tablet having a substantially V-shapedrecordgroove of uniform depth and constant efiective width, theundulations of which are formed directly in accordance-with thevibrations from a source of sound.

7. A sound-record consisting of a tablet having a record-groove ofconstant efiective width produced by crushing out and removing thematerial to produce lateral undulations by and in accordance withsoundwaves.

8. A sound-record consisting of a tablet having a record-groove ofconstantefiective width formed from a similar record-groove produced bycrushing out and removing the material to produce lateral undulations byand in accordance with sound-waves.

9. A sound-record consisting of a tablet having a record-groove formedtherein by crumbling the material and removing it from the tablet by andin accordance with sound-waves.

10. A sound-record consisting of a tablet having a record-groove formedfrom. an original record-groove produced by crumbling out the materialof a suitable recordtablet and removing it therefrom by and inaccordance with sound-Waves. i

11. Asound-record consisting of a tablet having a record-groove ofsubstantially uniform depth and of constant efiective width, theundulations of which are formed directly in accordance with thevibrations from a source of sound.

12. A sound-record consisting of a tablet having a zigzag record-grooveof substantially uniform depth and of constant efiective width, theundulations of which are formed directly in accordance with thevibrations from a source of sound.

Intestimony whereof I have signed this specification in the presence oftwo subscribing witnesses.

VICTOR H. EMERSON.

I Witnesses:

C. A. L. MASSIE, RALPH L. Sco'rr.

